This disclosure relates to systems and methods for improving the ability to pack a human-powerable wheeled vehicle when it is not being ridden. Human-powerable wheeled vehicles can include unicycles, bicycles, tricycles, quadricycles, wheelchairs, strollers, and powered versions of these vehicles (such as e-bikes) that can use human power in addition to other power sources, such as electricity and gasoline engines.
Human-powerable vehicles typically use space frame geometries for strength and stiffness to minimize weight, but space frame structures occupy a large volume, which is undesirable for storage and transport. Wheels that have spokes in tension between a hub and a rim are an example of a space frame that is difficult to pack due to the conical bulge and axle in the wheel center (hub region). Two assembled wheels with conical centers do not easily pack together into a small space. Separately, however, the wheel components (spokes, rims, tires, and hubs) occupy little volume before being assembled as a wheel.
Wheeled human-powerable vehicles might need to be moved long distances by cars, public transit (buses, trains, etc.), airplanes, boats, or other modes of transport. In such situations, it is beneficial for the bike (or similar) to be packed, protected from impact, and covered to protect other luggage from sharp or dirty elements of the bike. The packed human-powerable vehicle might also need to be carried or rolled in a “packed mode” in places such as an airport, bus terminal, or train station. Additionally, such vehicles in a compact configuration can be stored and locked more easily than when in a “ready to ride mode”.
One example is the transport of bicycles on commercial aircraft. In the past, airlines allowed passengers to check bicycles at no extra charge and even supplied free bicycle boxes. Now, many airlines charge for each piece of checked luggage. They charge even more for oversize items (typically specified as length+width+height greater than 62 linear inches) and/or overweight items (typically more than 50 pounds). Airlines might refuse to take the bike or other human-powered vehicle if not properly packed. The airline is generally not responsible for damage during transit. Observation of how luggage is handled shows that a packed bike must be able to take impacts from all directions. The packed unit must be openable and searchable by airport security personnel. The objective is a safely and securely packed bike (or similar) that fits the 62 linear inch limit and weighs as little as possible.
Folding bike embodiments with small wheels and tires (20 inch or less) generally don't perform as well on a variety of road surfaces and terrain as bicycles with full-size wheels. In this disclosure, full-size wheels are defined as wheels with a nominal outside tire diameter of 24 inches or greater and small wheels have tires nominally 20 inches in diameter or smaller. Here is a list of common small and full wheel and tire sizes:
Common name(nominal outsideBead seat diameterdiameter of tire)Outside diameter of rim(inside diameter of tire)700C/29inch648 mm(25.5 inches)622 mm(24.5 inches)650B/27.5inch610 mm(24 inches)584 mm(23 inches)26inch585 mm(23 inches)559 mm(22 inches)24inch533 mm(21 inches)507 mm(20 inches)20inch477 mm(19 inches)451 mm(18 inches)20inch432 mm(17.75 inches)406 mm(16.25 inches)16inch375 mm(14.75 inches)349 mm(13.75 inches)
Some bicycles with small wheels use ingenious folding arrangements to convert from a compact to a ridable configuration quickly, cleanly, and without the use of tools. Some small wheel bikes fold small enough to fit into a rectangular volume that meets the 62 linear inch size requirement and 50-pound weight limit. It is much easier to fit into 62 linear inches when the wheel is less than one third of the total length+width+height, which is what occurs when the nominal outside diameter of the tire is 20 inches or less.
There are bicycles with full-size wheels that can pack into the 62 linear inches, but these bicycles require time, tools, and expertise to disassemble and reassemble. Packing these bikes with full-size wheels into 62 linear inches is difficult. Referring to the list of bike wheel sizes, a typical road bike uses 700C wheels, with an outside tire diameter between 27 and 29 inches, and an outside rim diameter of approximately 25.5 inches. Thus, the typical target packed size for these bikes is 26×26×10 inches. It takes removing the air from the tires, many disassembly steps, detailed instructions, tools, covers to wrap each part, and patience to pack all the parts into these dimensions and prevent damage in transport.
One problem with trying to fit a bike with full-size wheels into the airline maximum of 62 linear inches is that the wheels are both large in diameter and fat in the center due to the use of tension spokes in a triangular configuration, when looked at in cross section or a conical configuration when viewed three dimensionally. The spokes typically terminate in a set of holes in one plane in the rim and terminate in two parallel planes in a circular configuration in the hub. When looked at in cross section this looks like a triangle that is wide at the hub and narrow at the rim. When two wheels with fat centers are put into a 26×26×10 inch case, there is little room for anything else. Space saved by having the wheels stored more compactly could simplify packing the other bicycle parts. It is known to have wheels that are disassemblable to save space, but disassemblable wheels typically do not use spokes in tension in a triangular/conical configuration. Wheels with triangular/conical tension spokes in are desired because this space frame configuration has a high strength to weight ratio, and weight is paramount for a human-powerable vehicle.
Many bicycles that are transported as checked luggage require a structural case, which adds to total luggage weight. There is also the issue of what to do with the case when one arrives at a destination and wants to start riding. It is better if the bike is packable in a compact arrangement that needs minimal or no external container solely for transport.
To summarize, the goal is a system/method for packing a human-powerable vehicle that (a) fits the entire vehicle/bike into one piece of luggage, is (b) lightweight, (c) fits within applicable size restrictions, (d) is quick to pack and unpack; and (e) requires minimal tools and packaging. (f) Ideally, such a system would not require a separate structural suitcase.
It should be understood that the drawings are not necessarily to scale. In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may have been omitted. It should be understood that the invention is not necessarily limited to the particular embodiments illustrated herein.